In 1767, the 11-year-old composer Wolfgang Amadeus Mozart was struck by smallpox. Like all smallpox victims, he was at serious risk of dying, but he survived the disease. This article discusses smallpox as it existed in Mozart's time, the decision taken in 1764 by Mozart's father Leopold not to inoculate his children against the disease, the course of Mozart's illness, and the aftermath.
Smallpox in Mozart's day
Smallpox in 18th-century Europe was a devastating disease, recurring frequently in epidemics and killing or disfiguring millions of people. The 18th century was probably a particularly terrible time for smallpox in Europe: urbanization had increased crowding, making it easier for the disease to spread; yet effective protection from smallpox through a smallpox vaccine was discovered only at the end of the century (see below).
The disease was a terrible one for its victims. Ian and Jenifer Glynn write: So what was it like? As children, we were told it was like chickenpox but worse. In fact it is not related to chickenpox, and it was unimaginably worse. In an unvaccinated population, something like 10–30 percent of all patients with smallpox would be expected to die. And dying was not easy; smallpox was, as Macaulay wrote, 'the most terrible of all the ministers of death.'
Those who survived smallpox did not always survive intact; it frequently inflicted blindness on its survivors. The survival rate was particularly low for children.
The physical appearance of the disease was frightening to patients and to their caretakers: the patient's skin became covered with large, bulging pustules, which often left conspicuous pitting on the skin of patients who survived the disease.
Leopold's decision against inoculation
Medicine had made only slight progress against the disease in Mozart's time. Around the second decade of the 18th century the method of inoculation, which had originated in Asia, reached European countries. Inoculation was not the same as the vaccination which later succeeded in eradicating the disease; rather, an inoculated person was treated with live smallpox virus, taken from pustules of the mildest variety of smallpox that could be found.
Inoculation offered immunity to smallpox, but the procedure carried a definite risk that the inoculated person could die from smallpox as a result. Thus, many parents felt that they would rather do nothing, risking future smallpox arriving at random, rather than carry out a deliberate act that might well kill their children immediately.
As Mozart biographer Ruth Halliwell points out, it is in this context that we must interpret a letter sent by Leopold Mozart on 22 February 1764 to his landlord and friend Lorenz Hagenauer concerning smallpox: They are trying to persuade me to let my boy be inoculated with smallpox. But as I have expressed sufficiently clearly my aversion to this impertinence they are leaving me in peace. Here inoculation is the general fashion. But for my part I leave the matter to the grace of God. It depends on His grace whether He wishes to keep this prodigy of nature in this world in which He placed it or to take it to Himself.
From the modern perspective—with most children now made safe from several terrible diseases by vaccination—it is easy to make the superficial interpretation that Leopold was acting foolishly, relying on divine will when direct action was available that would have helped his children. However, since in Leopold's day it was not firmly established that inoculation was beneficial, his remarks can be seen to be more of appeal to religion to resolve what must have seemed an impossible dilemma.
Mozart's case of smallpox
The Mozart family (Wolfgang, his father Leopold, his mother Anna Maria, and his older sister Nannerl) left their home in Salzburg for Vienna on 11 September 1767. They had been there before, exhibiting the children's talents, in 1762; by this time they had completed their "Grand Tour" of Europe, performing in England, France, and elsewhere, and hoped to achieve even greater recognition (and income) in the Imperial capital. The forthcoming marriage of the 16-year-old Archduchess Maria Josepha, daughter of Empress Maria Theresa, scheduled for October 14, promised many festivities and thus opportunities for visiting musicians.